(i) Field of the Invention
The present invention relates to an erroneous opening prevention mechanism for a grand piano lid.
(ii) Description of the Related Art
As shown in FIG. 5, while performing on a grand piano 100, the lid 110 of the grand piano 100 is usually raised via a side root hinge 146 and supported with a long or short lid prop 120 such that the lid remains open at a desired angle. Alternatively, when a lowered volume is required while performing on the grand piano 100, the lid 110 is closed, or laid flat on a grand piano main body 140, as shown in FIG. 6.
The grand piano 100 is provided with a music desk 130 under the lid 110 on the keyboard 150 side. Therefore, in order to allow use of the music desk 130 even with the lid 110 closed, as shown in FIG. 6, the lid 110 comprises a front lid 112 covering the music desk 130 and a back lid 114 connected with each other by a not shown hinge, whereby the front lid 112 can be folded back onto or over the back lid 114.
At the time of performing on the grand piano 100 with the lid 110 raised, as shown in FIG. 51 the front lid 112 is to be folded back onto or over the back lid 114 before raising the lid 110. This is because raising the lid 110 without first folding back the front lid 112 causes the heavy front lid 112 to be supported by only the hinge (not shown) attached to the back lid 114, since the lid prop 120 merely supports the back lid 114.
However, in the case where a person who is inexperienced in handling the grand piano 100 sets the grand piano 100 in a, concert hall, for example, the lid 110 is sometimes raised without first folding back the front lid 112.
Therefore, piano makers usually adopt safety measures, such as providing a large number of hinges, in preparation for a case like the above. Such measures, however, result in an additional cost as well as unsightly appearance for the grand piano 100.
Wherefore, an object of the present invention is to provide an erroneous opening prevention mechanism for preventing a grand piano lid from being raised without first folding back a front lid.
To attain this and other objects, the present invention discloses a grand piano comprising a combined lid fixed to a piano main body such that the lid is raised at a desired angle relative to the piano main body or laid flat on the piano main body, the combined lid including a back lid and a front lid foldable onto or over the back lid, the grand piano being provided with erroneous opening prevention means for preventing the lid from being raised without first folding back the front lid onto or over the back lid.
Also, an erroneous opening prevention mechanism, according to the present invention, comprises first locking means fixed to the front lid and second locking means fixed to the piano main body, and may be adapted such that when the front lid is unfolded and the lid is laid flat to cover the piano main body, the first locking means and the second locking means lock with one another to prevent the lid from being raised from the piano main body, and when the front lid is folded back onto the back lid, the first locking means and the second locking means are released from one another to allow the lid to be raised from the piano main body.
If an attempt to raise the lid is made without first folding back the front lid, the first locking means is caught in or engaged with the second locking means and, therefore, the lid cannot be raised. If the front lid is first folded back, however, the first locking means and the second locking means are released from one another and, therefore, the lid can be raised.
In this case, it is preferable that the first locking means is disposed in the vicinity of the fold line along which the front lid is folded back onto or over the back lid. When the first locking means is disposed as above, the moment against the fold line area (the moment generated by the front lid spontaneously falling in the opposite direction to the direction in which the front lid is folded back onto or over the back lid) is small. Accordingly, only a relatively small load is imposed on the fold line area, and related problems, such as loosening, are prevented from being caused. Specifically, in the case where a hinge is used in the fold line area, it is possible to prevent the hinge from becoming loose.